To reduce the risk of transfusion-associated graft vs. host disease in at-risk patients, red blood cells are irradiated before transfusion. The Canadian Standards Association issues guidelines regarding storage of irradiated red blood cells, but quality control tests are not performed on these units, so there are limited data on the quality of irradiated units or the appropriateness of the guidelines.
Canadian Blood Services’ ambitious project investigating the relationship between product quality and the timing of irradiation was the largest-to-date on this topic. The quality of 896 red blood cells in SAGM, irradiated between storage days 8 and 40 and stored in line with current Canadian guidelines, was assessed. The result: forty (4.5 %) of the units tested had levels of damage that would be unacceptable for transfusion based on Canadian guidelines. The most important factor predicting the amount of damage was storage time after irradiation.
In 2013 alone, Canadian Blood Services provided over 57,000 irradiated red blood cell units. This Canadian Blood Services research showed that Canadian guidelines on irradiation of red blood cells may not be enough to ensure transfusion of high quality units. Based on these data, amendment of the Canadian Standards Association guidelines on red blood cell irradiation, including timing and storage, will be part of the next revision (due 2018). Some provinces have already revised their transfusion medicine guidelines and a National Advisory Committee on Blood and Blood Products working group is drafting interim guidelines informed by these research findings.